Firing mechanism



June 10, 1030. G M, MCCANN i AL 2,044,008

FIRING MECHANISM Filed Oct. 18, 1954 W KT? Inventor; a M-Mc I'Iann hl er Charles T-Kn 120/ MW 7 Atturne Patented June 16, 1936 UNETED STATES PATENT OFFICE FIRING MECHANISM George M. McCann, New Castle, Del., and Charles T. Kohler, Watervliet, N. Y.

Application October 18. 1934, Serial No. 748,866

8 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon.

This invention relates to a firing mechanism for cannon.

The purpose of the invention is to provide a firing mechanism which may be conveniently mounted in the breech ring of a cannon.

Further objects of the invention are to provide novel means for retaining the various parts of the mechanism and for locking the hammer in various positions of adjustment.

With the foregoing and other objects in view, the invention resides in the novel arrangement and combination of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed 20 may be made within the scope of what is claimed without departing from the spirit of the invention.

A practical embodiment of the invention is illustrated in the accompanying drawing, where- 1n:

Fig. 1 is a view in side, elevation of a breech ring showing the firing mechanism in partial longitudinal section and the hammer locked in the cooked position.

Fig. 2 is a view in rear elevation with parts in section.

Fig. 3 is a sectional view on the line 3-3 of Fig. 2 showing the hammer locked.

Fig. 4 is a sectional view on the line 44 of Fig. 1.

Fig. 5 is a sectional Fig.2.

Fig. 6 is a fragmentary view partly in side elevation and partly in section showing the bolt 40 in unlocked position.

Referring to the drawing by characters of reference, there is shown the breech ring 5 of a gun in which a vertically sliding breech block 6 is mounted in the usual manner. A plate I mounted on the under side of the breech ring through a tongue and groove connection 8 is held in place by a key 9 extending transversely of the breech ring and plate and disposed in aligned grooves respectively 5 and l formed therein. 50 The plate serves the usual purpose of confining a breech block operating shaft H] which is supported in partial bearings H in the breech ring.

The shaft l2 inserted in the breech ring from the under side and passing through the plate I, is provided with a shoulder l3 for engageview on the line 5-5 of ment by the key 9 which thereby serves to hold the shaft against withdrawal. The shaft includes a pinion 54 adapted to be engaged by a rack 5. The rack is contained in a passage l6 formed in the breech ring above the key 9 and 5 is normally urged towards the outer side of the breech ring by a spring ll housed in the passage and seated on the inner end 18 of the passage.

The breech ring is formed with a slot 19 in 10 line with the upper part of the shaft and in line with the firing pin 29 of the breech block when the block is closed. A hammer 2| movable in the slot has a hub 22 squared on the upper part of the shaft so that it is rotatable with the shaft. 15 The hammer is movable through substantially ninety degrees and is in the cooked position when parallel to the axis of the gun with its shank brought up against the outer wall 23 of the slot is as seen in full lines in Fig. 3. The hammer when against the wall 23 serves as a stop to limit rotation of the shaft 12 under the action of the spring-pressed rack.

The upper face of the hub 22 of the hammer is formed with diametral intersecting grooves 24 25 and 25 adapted to receive a bolt 26 mounted in the breech ring and serving to lock the hammer in either of two positions. The bolt is formed with a segment cut away to provide a face 21 which has a reduced radius whereby in one position of angular displacement of the bolt, it will be clear of the hub of the hammer and will not interfere with rotation thereof.

An arm 28 on the outer end of the bolt 26 is disposed in a recess 29 in the side of thebreech ring and carries a plunger 30 normally urged inwardly towards the breech ring by means of a spring 3 I. The inner end of the plunger is adapted to selectively enter either one of two openings 32 and 33 spaced ninety degrees apart.

As shown in Fig. 6 when the plunger is in the opening 32, the face 21 of the bolt is presented towards the hub of the hammer and the bolt is therefore inoperative while the hammer is operative. As shown in Figs. 1 and 3, when the plunger is in the opening 33, the bolt is engaged in one of the grooves 24 and 25 of the hub and the hammer is locked against movement. The bolt is engaged in the groove 24 to hold the hammer in the cooked position (Fig. 3) and it is engaged in the groove 25 to hold the hammer just out of the firing position as indicated in dotted lines in Fig. 3. This latter adjustment is employed to protect the hammer when the gun is in travel.

The bolt is conveniently held against axial displacement by the shaft I2 which has a reduced extremity 34 engageable in a peripheral groove 35 in the bolt.

A pair of trigger arms 36 and 3'! on the lower end of the shaft I2 are respectively equipped with lanyards or operating members 38 and 39 whereby the shaft [2 may be rotated from either side of the gun.

The spring pressed rack l5 normally rotates the a shaft [2 to maintain the hammer 2| in the cocked position. The shaft I2 is counterrotated by acting on the trigger arms 36 and 31 to swing the hammer to firing position.

We claim: 7

1. In a gun, a breech ring, a plate on the under side of the ring, a key retaining the plate in place on the breech ring, a shaft inserted in the breech ring through the plate and held against axial displacement by the key, a trigger arm on the lower end of the shaft, a pinion on the shaft, a rack mounted in the breech ring. and meshing with the pinion, a spring normally urging the rack in one direction, a hammer fixed to the upper end of the shaft and having a hub with intersecting grooves on its upper face, a bolt mounted in the breech ring above the hub of the hammer and held against axial displacement by the shaft, said bolt clearing the hammer in one position of adjustment and in another position selectively receivable in the grooves of the hammer depending on the position of the hammer, and means for locking the bolt against rotation.

. 2. In a gun, a breech ring, a plate on the under side of the ring, a key retaining the plate in place on the breech ring, a shaft inserted in the breech ring through the plate and held against axial displacement by the key, a pinion on the shaft, a rack mounted in the breech ring and meshing with the pinion, a spring normally urging the rack in one direction, a hammer fixed to the upper end of the shaft and having a hub with intersecting grooves on its upper face, a bolt mounted in the breech ring above the hub of the hammer and held against axial'displacement by the shaft, said bolt clearing the hammer in one position of adjustment and in another position selectively receivable in the grooves of the hammer depending on the position of the hammer.

3. In a gun, a breech ring, a plate on the under side of the ring, a key retaining the plate in place on the breech ring, a shaft inserted in the breech ring through the plate; a pinion on the shaft, a

' rack mounted in the breech ring and meshing with the pinion, a spring normally urging the rack in one direction, a hammer fixed to the the breech ring, a pinion on the shaft, a rack mounted in the breech ring andmeshing with the pinion, a spring normally urging the rack in one direction, a hammer fixed to the shaft and having a hub'with intersecting grooves on one face, a bolt mounted in the breech ring and held against axial displacement by the shaft, said bolt clearing the hammer in one position of adjustment and in another position selectively receivable in the grooves of the hammer depending on the position of the hammer, and means for rotating the shaft against the action of the rack.

5. In a gun, a breech ring, a shaft mounted in the breech ring, a pinion on the shaft, a rack mounted in the breech ring and meshing with the pinion, a spring normally urging the rack in one direction, a hammer fixed to the shaft and having a hub with intersecting grooves on one face, a bolt mounted in the breech ring, said bolt clearing'the hammer in one position of adjustment and in another position selectively receivable in the grooves of the hammer depending on the position of the hammer, and means for rotating the shaft against the action of the rack.

6. In a gun, a breech ring, a shaft mounted in the breech ring, a hammer fixed on the shaft and having a hub with grooves on one face, a bolt mounted in the breech ring and held against axial displacement by the shaft, said bolt clearing the hammer in one position of adjustment and in another position selectively receivable in the I grooves of the hammer depending on the position of the hammer, and means for rotating the shaft.

'7. In a gun, a breech ring, a shaft mounted in the breech ring, a hammer fixed on the shaft and having a hub with grooves on one face, a bolt mounted in the'breech ring, said bolt clearing the hammer 'in one position of adjustment and in another position selectively receivable in the grooves of the hammer depending on the position of the hammer, and means for rotating the shaft j 8. In a gun, a breech ring, a plate on the under side of the ring, a key retaining the plate in place on the ring, a shaft inserted in the breech ring through the plate and held against axial displacement by the key, and a hammer on the shaft.

' GEORGE M. McCANN. CHARLES 'I. KOHLER. 

